Description
In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: validate DRAW_PRIMITIVES header size before division vmw_cmd_draw() computes maxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl); where header->size is u32 and is taken straight from the user-supplied command stream. When header->size is less than sizeof(cmd->body) the unsigned subtraction wraps to nearly 4 GiB, producing a huge maxnum. Any user-controlled cmd->body.numVertexDecls then passes the bound and the loop dereferences decl[i] far past the end of the kernel command bounce buffer, producing an out-of-bounds read of kernel memory. Reject undersized headers up front.
References8
- git.kernel.org/stable/c/112c6ff29a56f3a22db4d5af869697aa07035ad6
- git.kernel.org/stable/c/2666cddf0dd218aa9bd1f99db688d1b532eac21a
- git.kernel.org/stable/c/85891d174707d8bddcec7a888fb4e1d17def34f3
- git.kernel.org/stable/c/b89ca4bba820f79dde52af15ee139fe6e8bbc314
- git.kernel.org/stable/c/bef30317fcb4c838a37bceb2fc76256eb6b975c1
- git.kernel.org/stable/c/c77cf8edae2bd3a1599115301cc7c98d0c78e731
- git.kernel.org/stable/c/dc0be7662b7b0ce28cb5eea864737793ed7b9e70
- git.kernel.org/stable/c/fc0c02f510e41650df3479f96e257acf87d8a20a
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 11 November 2026
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.